Engine starter gearing



1959 J. J. DlGBY 2,914,951

ENGINE STARTER GEARING Filed Feb. 14. 1958 mmyrm BY 414:). Jazz. M j

A TORNEY patfint 2,914,951 ENGINE STARTER GEARING James J. Digby, Elmira, N.Y., assignor to Bendix Aviation CorporatiomElmira Heights, N.Y., a corporation of Delaware Application February 14, 1958, Serial No. 715,397

6 Claims. (Cl. 74-9) The present invention relates to engine starter gearing and more particularly to a simplified light-duty form of drive particularly well adapted to start small internal combustion engines such as outboard marine engines.

It is an object of the present invention to provide a novel drive of this type which is efficient and reliable in operation and simple and economical in construction.

It is another object to provide such a device employing a pin and inclined slot type of traversing structure for the starting pinion, in which the traversing pin serves also to actuate a yielding driving connection.

Further objects and advantages will be apparent from the following description taken in connection with the accompanying drawing in which:

Fig. 1 is a side elevation partly broken away and in section of a preferred embodiment of the invention showing the parts in idle position;

Fig. 2 is a similar view showing the position;

Fig. 3 is a detail in side elevation of the inner traversing sleeve; and

Fig. 4 is a view similar to Fig. 3 of the outer driving sleeve.

In Fig. 1 of the drawing there is illustrated a power shaft 1 having a smooth reduced extension 2 on which a pinion 3 is slidably journalled for movement into and out of mesh with a gear 4 of the engine to be started. Means for traversing the pinion 3 into mesh with the engine gear 4 is provided comprising a pin 5'fixedly mounted in the power shaft 1 and projecting radially therefrom into a cam slot 6 of a traversing sleeve 7 which is slidably journalled on the power shaft 1. Sleeve 7 is formed with a radial flange 8 which is slidably received in a barrel member 9 fixed to the pinion 3 in any suitable manner as indicated at 11. The flange 8 has a thrust connection with the closed end of the barrel, a thrust washer 12 being interposed if deemed desirable.

Yielding means are provided for rotating the pinion 3 comprising an outer sleeve member 13 bearing on the traversing sleeve 7 having a spiral slot 14 which slidably receives the projecting end of the pin 5. The slot 14 is open at one end in order to facilitate assembly of the parts, and extends at its other end a substantial distance further than the slot 6 in the inner sleeve 7. Sleeve 13 is formed with a radial flange 15 having lugs 16 slidably received in axial slots 17 in the open end of the barrel 9 so as to form a splined connection between said outer sleeve and the barrel. The sleeve 13 is maintained in the barrel by means of a lock ring 18.

The cam slot 6 in the inner traversing sleeve 7 is of such axial length as to limit the longitudinal travel of the inner sleeve 7 to that necessary to traverse the pinion 3 into and out of mesh with the engine gear 4. The idle position of the pinion 3 is defined by the seating of the pin 5 in the adjacent end of the slot 6, where it is normally held by an anti-drift spring 19 bearing parts in cranking 2,914,951 Patented Dec. 1, 1959 ice against the pinion at one end and at its other end against a thimble 21 fixed on the power shaft by means of a lock ring 22.

Telescoping movement of the two sleeves 7, 13 is yieldingly opposed by an annular body 23 of elastically deformable material interposed between said two flanges 8, 15 and preferably maintained under initial compression by means of the lock ring 18.

In operation, starting with the parts inthe positions illustrated in Fig. 1, rotation of the power shaft in the direction of the arrow causes the pin 5 to traverse the cam slot 6 in the inner sleeve 7 and thereby move the entire assembly to the right until such motion is arrested by the engagement of the pin 5 with the opposite end 24 of the cam slot 6 as shown in Fig. 2, at which time the pinion 3 is meshed with the engine gear 4. Upon further rotation of the power shaft, the inner sleeve 7 is forced to rotate therewith by means of the pin 5, but the outer sleeve 14 is not so positively driven since its spiral slot 14extends further to the left than that of the cam slot 6. The sleeve 13, the rotation of which is resisted by its splined connection 16, 17 with the barrel 9 and pinion 3, consequently moves further to the right, thereby compressing the yielding member 23 which cushions the building up of the cranking torque to the pinion.

When suflicient torque has thus been built up, the pinion will be rotated to crank the engine, and when the engine fires the pinion and sleeve assembly will be traversed back to its idle position by the overrunning of the cam slot 6 on the pin 5 after which it will be maintained in its idle position by the anti-drift spring 19.

Although but one form of the invention has been shown and described in detail, it will be understood that changes may be made in the precise form and arrangement of the parts without departing from the spirit of the invention.

I claim:

1. In an engine starter drive a power shaft, a pinion slidably journalled thereon for movement into and out of mesh with a gear of an engine to be started, means for traversing the pinion on the shaft including a sleeve slidably journalled on the shaft having a cam slot formed therein and a pin fixed in the shaft traversing said slot, a barrel member fixed to the pinion surrounding the sleeve, said sleeve being formed with a flange having a thrust engagement with the barrel, and means for rotating the barrel including a second sleeve surrounding the first sleeve, non-rotatably connected to the barrel and having a spiral slot traversed by said pin, and yielding means resisting telescoping movement of said sleeves.

2. A device as set forth in claim 1 in which the cam slot in the first-mentioned sleeve extends axially therein for the desired axial travel of the pinion in its movement into and out of mesh with the engine gear, and cooperates with said pin to determine such axial travel.

3. A device as set forth in claim 2 in which the spiral slot in said second sleeve is of the same hand as the cam slot in the first sleeve and is of such axial extent as to prevent the pin from interfering with the axial movement of said second sleeve.

4. A device as set forth in claim 2 including further yielding means urging the pinion toward idle position, and means in said barrel for retaining said second sleeve therein.

5. A device as set forth in claim l in which said second sleeve is formed with a radial flange splined in said barrel, and the yielding means resisting telescoping movement of the sleeves is in the form of a body of elastically deformable material in the barrel surround-- '3 ing the sleeves and compressed between the flanges .of said sleeves.

6. In an engine starter drive, a power shaft, a pinion slidably journalled thereon, and means .for actuating the pinion from the shaft including a pin fixed in and protruding radially from the shaft, a barrel fixed to the pinion, a sleeve having a cam slot slidably receiving said pin and having a thrust connection to the pinion, a second sleeve splined in the barrel surrounding the first mentioned sleeve having a spiral slot receiving said pin, and yielding means resisting telescopic movement of the sleeves.

References Cited in the file of this patent UNITED STATES PATENTS 

